Improvement in double-seaming sheet metal



Barnum OFFICEa S. SVVEENEY AND S. PARKS, OF ROME, NEV YORK.

IMPROVEMENTIN DOUBLEw-SAMENG SHEET METAL.

Specification forming part of Letters Patent No. 32,799, dated July 9,1861.

To @ZZ whom. it may concern:

Be it known that We, STEPHEN SWEENEY- and STEPHEN PARKs, of the city of Rome, Oneida county, in the State ofNeW York, have jointly and together invented certain new and useful Improvements in Machinery for Double-Seaming Sheet Metal; and we do hereby declare that the following is a full and correct description thereof, reference being had to the annexed drawings, making a part of this specification, and to the letters of reference thereon.

Our improvements are especially designed for donbleseamingplates of tin or other sheet metal at right angles, or nearly so, either in straight or curved seams. Machines now'used for this purpose-such as the Olmstead machine, patented January 17, 1860-are expensive and complicated, and require a 1nachine made expressly for the purpose, which prevents general Aadoption of them by the trade, besides none of the machinery known to us performs the operation of bending over and swaging the seam at one operation.

The annexed drawings illustrate ourinvention.

Figure No. 1 represents a sectional view of the body and bottom of a circular vessel prepared i'or the operation of double-scanning; Fig. No. 2, a section ofthe same When the operation of doubleseaming is completed. l Letters a and b, Fig. No. 3, are heads or formers,\vl1ich may be iitted to the mandrels a' b/ of an ordinary stoveApipe-swaging machine, such as are in common use in tin-shops.

The red lines, letter O, represents avessel in tlieact of being double-seamed, the double seam being formed at d.

Our said invention consists in the relative arrangement and combination of the bending and suaging surfaces c and f of the heads or l formel-s a and Z1. rlhe surface c of the former l that acts on the inside of the seam is at an acute angle with a line drawn transversely to the axis of the mandrel. It therefore presses the metal outward and enlarges it at the point of making the seam, which would not be the ease if the surface were parallel With the axis. The surface f is peculiar in respect of combinin g the swaging and bending surfaceto Wit, a groove, g, and an inclined or curved flange, h, merged into each other. The inclined surface of the ilange bends over the double seam and the groove swages it. A seam formed in this manner may be made much tighter than in the usual mode of forming such seams, the inclination of the surfaces ot' the heads or formers permitting a cross-seam to pass between the heads freely, and therefore to be pinched down tightly at the point of intersection with the seamthat is being formed.

The shape of the groove and iiange surface admits of some moditication for the purpose of varying the form of the seam, and also of concaviug the bottom by changing the angle at which the seam is formed slightlyfrom a right angle. These modications are not necessary to be described here, being evident to mechanics accustomed to make or use machines for seaining sheet inet-al.

Vhat We claim as our invention and improveinent in machines for double-seaming sheet metal is The groove f/ on the roller a when the said groove terminates on its outer edge in the ele vated portion or inclined flange lL, in combination with the conical roller b, as and for the purpose above set forth.

STEPHEN SWEENEY. STEPHEN PARKS.

Vitnesses:

A. B. BLAIR, JNO. M. ODONNELL. 

